3D Nanochannel Interleaved Devices

ABSTRACT

3D nanochannel interleaved devices for molecular manipulation are provided. In one aspect, a method of forming a device includes: forming a pattern on a substrate of alternating mandrels and spacers alongside the mandrels; selectively removing the mandrels from a front portion of the pattern forming gaps between the spacers; selectively removing the spacers from a back portion of the pattern forming gaps between the mandrels; filling i) the gaps between the spacers with a conductor to form first electrodes and ii) the gaps between the mandrels with the conductor to form second electrodes; and etching the mandrels and the spacers in a central portion of the pattern to form a channel (e.g., a nanochannel) between the first electrodes and the second electrodes, wherein the first electrodes and the second electrodes are offset from one another across the channel, i.e., interleaved. A device formed by the method is also provided.

FIELD OF THE INVENTION

The present invention relates to nano-fabricated devices, and moreparticularly, to three-dimensional (3D) nanochannel interleaved devicesfor molecular manipulation using dipole moments.

BACKGROUND OF THE INVENTION

Molecular-level control of compounds has important applications in avariety of fields. In medicine, for instance, manipulation of moleculesat the molecular level can be used to control the composition ofmedications. Such a fine-tuned control over the composition ofmedications can enable the creation of customized medicines and specificdosing. Further, molecular-level control can provide more efficientdelivery systems for medications, thus advancing treatment options andefficacy.

However, the ability to effectively manipulate molecules at themolecular level remains challenging and difficult. Technology does notcurrently exist for production-scale molecular manipulation.

Accordingly, improved techniques for efficient and effectivemanipulation of molecules at the molecular level would be desirable.

SUMMARY OF THE INVENTION

The present invention provides three-dimensional (3D) nanochannelinterleaved devices for molecular manipulation. In one aspect of theinvention, a method of forming a device for molecular manipulation isprovided. The method includes: forming a pattern on a substrate ofalternating mandrels and spacers alongside the mandrels; selectivelyremoving the mandrels from a front portion of the pattern forming gapsbetween the spacers; selectively removing the spacers from a backportion of the pattern forming gaps between the mandrels; filling i) thegaps between the spacers with a conductor to form first electrodes andii) the gaps between the mandrels with the conductor to form secondelectrodes; and etching the mandrels and the spacers in a centralportion of the pattern to form a channel (e.g., a nanochannel) betweenthe first electrodes and the second electrodes, wherein the firstelectrodes and the second electrodes are offset from one another acrossthe channel, i.e., interleaved.

In another aspect of the invention, a device is provided. The deviceincludes: a channel (e.g., a nanochannel); first electrodes disposed inbetween spacers on a first side of the channel; and second electrodesdisposed in between mandrels on a second side of the channel, whereinthe first electrodes and the second electrodes are offset from oneanother across the channel, i.e., interleaved.

A more complete understanding of the present invention, as well asfurther features and advantages of the present invention, will beobtained by reference to the following detailed description anddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a three-dimensional diagram illustrating mandrels having beenformed on a substrate according to an embodiment of the presentinvention;

FIG. 2 is a three-dimensional diagram illustrating spacers having beenformed on opposite sides of the mandrels according to an embodiment ofthe present invention;

FIG. 3 is a three-dimensional diagram illustrating spaces between thespacers alongside adjacent mandrels having been filled with additionalmandrel material according to an embodiment of the present invention;

FIG. 4 is a three-dimensional diagram illustrating a mask having beenformed over back and central portions of the pattern, and an etch havingbeen performed to selectively remove the mandrels from a front portionof the pattern creating gaps between the spacers according to anembodiment of the present invention;

FIG. 5 is a three-dimensional diagram illustrating the gaps between thespacers having been filled with a sacrificial material according to anembodiment of the present invention;

FIG. 6 is a three-dimensional diagram illustrating the mask having beenremoved according to an embodiment of the present invention;

FIG. 7 is a three-dimensional diagram illustrating a channel spacerhaving been formed over the central portion of the pattern according toan embodiment of the present invention;

FIG. 8 is a three-dimensional diagram illustrating the spacers havingbeen removed from the back portion of the pattern creating gaps betweenthe mandrels according to an embodiment of the present invention;

FIG. 9 is a three-dimensional diagram illustrating the sacrificialmaterial having been selectively removed according to an embodiment ofthe present invention;

FIG. 10 is a three-dimensional diagram illustrating that the gapsbetween the spacers (in the front portion of the pattern) are offsetfrom the gaps between the mandrels (in the back portion of the pattern)according to an embodiment of the present invention;

FIG. 11 is a three-dimensional diagram illustrating the gaps between thespacers and the gaps between the mandrels having been filled with aconductor according to an embodiment of the present invention;

FIG. 12 is a three-dimensional diagram illustrating the channel spacerhaving been removed forming a trench in the conductor according to anembodiment of the present invention;

FIG. 13 is a three-dimensional diagram illustrating the spacers and themandrels in the central portion of the pattern having been removedthrough the trench forming a channel according to an embodiment of thepresent invention;

FIG. 14 is a three-dimensional diagram illustrating the conductor havingbeen recessed forming first/second electrodes on opposite sides of thechannel according to an embodiment of the present invention;

FIG. 15 is a top-down diagram illustrating that the first electrodes areoffset from the second electrodes across the channel according to anembodiment of the present invention;

FIG. 16 is a three-dimensional diagram illustrating that the firstelectrodes are offset from the second electrodes across the channelaccording to an embodiment of the present invention; and

FIG. 17 is a three-dimensional diagram illustrating that, duringoperation, an electric field applied to the first/second electrodes willelectrokinetically orient and/or locomote a polar molecule in thechannel according to an embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Provided herein are three-dimensional (3D) device structures formolecular manipulation that leverage the dipole within the molecule, aswell as current nanofabrication techniques to precisely manufactureextremely small features, e.g., dimensions ranging from severalmicrometers (μm) to 10's of nanometers (nm). Further, the presenttechniques improve resolution through the interleaving of 3D spirallylocated electrodes enabling a much finer level of control andmanipulation.

Namely, as will be described in detail below, advanced patterningtechniques are leveraged herein to place the (interleaved) electrodesfor field generation at precise locations at a molecular scale. Advancedetching techniques are used to precisely place channels of a nanoscalesize at the center of the electrodes. By ‘interleaved’ it is meant that,instead of being directly opposite one another, the electrodes onopposite sides of the nanochannel are offset from one another.

Advantageously, the present 3D device structures permit theelectro-kinetic control of individual molecules using the dipolesinherent in the subject material. For instance, during operation,applying a field selectively to portions of a molecule (via theelectrodes) will electrokinetically orient and/or locomote the moleculein the nanochannel as a result of dynamic electric field application.Individual electrodes can be controlled individually and intelligently.

An exemplary methodology for forming a 3D device for molecularmanipulation is now described by way of reference to FIGS. 1-17 . Asshown in FIG. 1 , the process begins with the formation of mandrels 104on a substrate 102.

According to an exemplary embodiment, substrate 102 is a bulksemiconductor wafer, such as a bulk silicon (Si), bulk germanium (Ge),bulk silicon germanium (SiGe) and/or bulk III-V semiconductor wafer.Alternatively, substrate 102 can be a semiconductor-on-insulator (SOI)wafer. A SOI wafer includes an SOI layer separated from an underlyingsubstrate by a buried insulator. When the buried insulator is an oxideit is referred to herein as a buried oxide or BOX. The SOI layer caninclude any suitable semiconductor, such as Si, Ge, SiGe, and/or a III-Vsemiconductor. Substrate 102 may already have pre-built structures (notshown) such as transistors, diodes, capacitors, resistors, isolationregions (e.g., shallow trench isolation (STI) regions), interconnects,wiring, etc.

To form the mandrels 104 on substrate 102, a mandrel layer is firstdeposited onto the substrate 102 and then patterned into the individualmandrels 104 shown in FIG. 1 . According to an exemplary embodiment,mandrels 104 are formed from an undoped oxide material. Suitable undopedoxide materials include, but are not limited to, undoped silicon oxide(SiOx). A process such as chemical vapor deposition (CVD), atomic layerdeposition (ALD) or physical vapor deposition (PVD) can be used todeposit the mandrel material.

Mandrels 104 can be patterned using a patterning technique such aslithography followed by an etching process. With a lithography andetching process, a lithographic stack (not shown), e.g.,photoresist/organic planarizing layer (OPL)/anti-reflective coating(ARC), is typically used to pattern a hardmask (not shown). The patternfrom the hardmask is then transferred to the underlying substrate (inthis case the mandrel layer). The hardmask is then removed. Suitableetching processes include, but are not limited to, a directional(anisotropic) etching process such as reactive ion etching (RIE).Alternatively, the mandrels 104 can be formed by other suitabletechniques, including but not limited to, sidewall image transfer (SIT),self-aligned double patterning (SADP), self-aligned quadruple patterning(SAQP), and other self-aligned multiple patterning (SAMP) techniques. Itis notable that the patterning of four mandrels 104 on substrate 102 inthe present embodiment is merely provided as an example meant toillustrate the present techniques. For instance, embodiments arecontemplated herein where more or fewer mandrels 104 than shown areformed on substrate 102.

According to an exemplary embodiment, mandrels 104 have nanoscaledimensions. Advantageously, use of the above-described pitch multiplyingtechniques such as SIT, SADP, SAQP or SAMP, permits the patterning ofmandrels at a sub-lithographic pitch (i.e., a pitch smaller than what isachievable using direct lithography. For instance, in one exemplaryembodiment, mandrels 104 have a height H of from about 20 nanometers(nm) to about 50 nm and ranges therebetween, a width W of from about 5nm to about 10 nm and ranges therebetween, and a pitch p of from about10 nm to about 20 nm and ranges therebetween. See FIG. 1 . Pitch isdefined as the distance from a given point on one mandrel to the samepoint on the adjacent mandrel.

Spacers 202 are then formed on opposite sides of the mandrels 104. SeeFIG. 2 . Preferably, the spacers 202 are formed from a differentmaterial than the mandrels 104 to provide etch selectivity between thespacers 202 and the mandrels 104. This etch selectivity will beleveraged later on in the process to remove (portions) of the mandrels104 selective to the spacers 202. As provided above, the mandrels 104can be formed from an undoped oxide material such as SiOx. In that case,a nitride material such as silicon nitride (SiN) and/or siliconoxynitride (SiON) can be used for the spacers 202 to provide etchselectivity vis-á-vis mandrels 104.

According to an exemplary embodiment, spacers 202 are formed bydepositing a spacer material (e.g., SiN and/or SiON—see above) onto themandrels 104. A process such as CVD, ALD or PVD can be used to depositthe spacer material. A directional (anisotropic) etching process such asRIE is then used to pattern the spacer material into the individualspacers shown in FIG. 2 . In one exemplary embodiment, spacers 202 havea width Wspacer of from about 5 nm to about 10 nm and rangestherebetween.

As shown in FIG. 2 , following placement of spacers 202 alongside themandrels 104, there is a space S present between the spacers 202alongside adjacent mandrels 104. As will be described in detail below,this space S will be filled with additional mandrel material in the nextstep.

It is notable, that the above-described process of placing mandrels 104and then spacers 202 alongside the mandrel can be repeated (in one ormore iterations), if so desired, to achieve denser patterning. In thatcase, although not explicitly shown in the figures, an oxide-selectiveetch can be used to remove the mandrels 104 selective to the spacers 202(see above). Additional spacers (not shown) can then be placed alongsidespacers 202, effectively doubling the pitch of spacers 202.

The spaces S between the spacers 202 alongside adjacent mandrels 104 arethen filled with additional mandrel material, forming mandrels 302. SeeFIG. 3 . According to an exemplary embodiment, mandrels 302 have thesame dimensions (i.e., height, width, pitch, etc.) as mandrels 104. Forclarity, mandrels 104 and mandrels 302 may also be referred to herein asfirst mandrels and second mandrels, respectively. As provided above,suitable mandrel materials include, but are not limited to, undopedoxide materials such as undoped SiOx. A process such as CVD, ALD or PVDcan be used to deposit the mandrel material into the spaces S. Followingdeposition, the mandrel material can be planarized using a process suchas chemical-mechanical polishing (CMP).

As shown in FIG. 3 , an alternating pattern 304 of spacers 202 andmandrels 104/mandrels 302 is now present on the surface of substrate102. Using the configuration above where the spacer material is anitride material (such as SiN and/or SiON) and the mandrels material isan oxide material (such as undoped SiOx) as an example, an alternatingnitride/oxide pattern is now present on the surface of wafer 102.

The next task is to selectively remove portions of the mandrels104/mandrels 302 from a (first) portion 402 of the pattern 304. To doso, a mask 406 is next formed masking/covering a (second) portion 403and a (third) portion 404 of the pattern. See FIG. 4 . As shown in FIG.4 , in the present example, the first portion 402 encompasses a frontportion of the pattern 304, the second portion 403 encompasses a centralportion of the pattern 304, and the third portion 404 encompasses a backportion of the pattern 304. As will be described in detail below, thefirst/front portion 402 and the third/back portion 404 of the pattern304 will be used to form interleaved/offset electrodes of the device. Achannel of the device will be formed in the second/central portion 403,between the first/front portion 402 and third/back portion 404electrodes.

According to an exemplary embodiment, mask 406 is formed by depositing ahardmask material onto substrate 102 over the pattern 304. Suitablehardmask materials include, but are not limited to, a carbon-containinghardmask material such as amorphous carbon. Use of a carbon-containinghardmask will enable the removal of mask 406 selective to the underlying(e.g., nitride) spacers 202 and (e.g., oxide) mandrels 104/mandrels 302.The hardmask material can be deposited using a process such asplasma-enhanced CVD (PECVD) or a casting process such as spin coating orspray coating. Lithography and etching techniques (see above) are thenemployed to pattern the hardmask material into the patterned mask 406shown in FIG. 4 .

An etch is next performed to selectively remove portions of the mandrels104/mandrels 302 from the first/front portion 402 of the pattern 304.According to an exemplary embodiment, a directional (anisotropic)etching process such as RIE is employed to remove the mandrels104/mandrels 302 from first/front portion 402. As provided above,mandrels 104/mandrels 302 can be formed from an oxide material such asSiOx. In that case, an oxide-selective RIE can be used to remove theportions of the mandrels 104/mandrels 302 from the first/front portion402 of pattern 304 selective to spacers 202. Notably, as shown in FIG. 4, mask 406 is present over and protecting the portions of the mandrels104/mandrels 302 in the second/central portion 403 and the third/backportion 404 of the pattern 304.

Removal of mandrels 104/mandrels 302 in this manner creates gaps 408between the spacers 202 in the first/front portion 402 of pattern 304.Ultimately, these gaps 408 will be filled with a conductor to form theelectrodes on one side of the channel. However, at this stage in theprocess, gaps 408 are first filled with a sacrificial material 502. SeeFIG. 5 . The term ‘sacrificial’ as used herein refers to the notion thatmaterial 502 will be used early on in the process to place a channelspacer, and then later removed and replaced with the electrodeconductor. See below. Suitable sacrificial materials include, but arenot limited to, amorphous silicon and/or poly-silicon. A process such asCVD, ALD or PVD can be employed to deposit the sacrificial material 502into the gaps 408. As shown in FIG. 5 , the deposited sacrificialmaterial 502 overfills the gaps 408 and is then planarized to the top ofmask 406. The sacrificial material 502 can be planarized using a processsuch as CMP.

Mask 406 is next selectively removed from the second/central portion 403and third/back portion 404 of the pattern 304 exposing the underlyingspacers 202/mandrels 104/mandrels 302. See FIG. 6 . As shown in FIG. 6 ,sacrificial material 502 remains in the first/front portion 402 ofpattern 304 filling the gaps 408 between the spacers 202. As providedabove, mask 406 can be formed from a carbon-containing hardmask materialsuch as amorphous carbon. Amorphous carbon is an ashable material. Thus,according to an exemplary embodiment, mask 406 is removed selective tothe underlying (e.g., nitride) spacers 202 and (e.g., oxide) mandrels104/mandrels 302 using oxygen-containing plasma ashing.

Removal of the mask 406 enables the placement of a channel spacer 702over the second/central portion 403 of the pattern 304 adjacent tosacrificial material 502. See FIG. 7 . Namely, as provided above, mask406 had been present over the second/central portion 403 and third/backportion 404 of the pattern 304 in which a channel and electrodes of thedevice will be formed, respectively. Removal of the mask 406 is neededso that the full height channel spacer 702 (relative to the top ofsacrificial material 502) can be formed. Suitable materials for thechannel spacer 702 include, but are not limited to carbon-containingspacer materials such as amorphous carbon. Use of a carbon-containingspacer material will enable the selective removal of sacrificialmaterial 502 (e.g., amorphous silicon and/or poly-silicon) later on inthe process (see below). The spacer material can be deposited using aCVD process such as PECVD or a casting process such as spin coating orspray coating. Lithography and etching techniques (see above) can thenbe employed to pattern the spacer material into the channel spacer 702shown in FIG. 7 .

In one embodiment, the channel of the device has nanoscale dimensions,i.e., the device has a nanochannel. In that case, according to anexemplary embodiment, channel spacer 702 has a width Wchannel spacer offrom about 2 nm to about 10 nm and ranges therebetween. See FIG. 7 .

With sacrificial material 502 covering the first/front portion 402 andchannel spacer 702 covering the second/central portion 403 of pattern304, an etch is next performed to selectively remove portions of thespacers 202 from the third/back portion 404 of the pattern 304. See FIG.8 . According to an exemplary embodiment, a directional (anisotropic)etching process such as RIE is employed to remove to the portions of thespacers 202 from third/back portion 404. As provided above, spacers 202can be formed from a nitride material such as SiN and/or SiON. In thatcase, a nitride-selective RIE can be used to remove the portions ofspacers 202 from the third/back portion 404 of pattern 304 selective to(e.g., oxide) mandrels 104/mandrels 302.

Removal of spacers 202 in this manner creates gaps 802 between themandrels 104/mandrels 302 in the third/back portion 404 of pattern 304.Later in the process, these gaps 802 will be filled with a conductor toform the electrodes on one side of the channel. Notably, the mandrels104/mandrels 302 in the third/back portion 404 of pattern 304 are offsetfrom the spacers 202 present in the first/front portion 402 of pattern304. Thus, as will be described in detail below, electrodes formed inthe gaps 802 too will be offset from the electrodes formed (on anopposite side of the channel) in the gaps 408 (see, e.g., FIG. 4—described above) between spacers 202. As highlighted above, havingoffset or interleaved electrodes is a unique aspect of the presentdevice design that advantageously improves resolution thereby enabling amuch finer level of control and manipulation of molecules.

Next, sacrificial material 502 is selectively removed from thefirst/front portion 402 of pattern 304 and from in between spacers 202.See FIG. 9 . As shown in FIG. 9 , removal of sacrificial material 502re-opens gaps 408 between spacers 202. According to an exemplaryembodiment, a directional (anisotropic) etching process such as RIE isemployed to remove sacrificial material 502. As provided above, suitablematerials for sacrificial material 502 include, but are not limited to,amorphous silicon and/or poly-silicon. In that case, a silicon-selectiveRIE can be used to remove sacrificial material 502 selective to (e.g.,nitride) spacers 202, (e.g., oxide) mandrels 104/mandrels 302, and(e.g., amorphous carbon) channel spacer 702.

As shown in FIG. 9 , channel spacer 702 remains covering thesecond/central portion 403 of pattern 304. However, for clarity, if onewere to visualize the structure looking through the channel spacer 702(see FIG. 10 where channel spacer 702 is shown transparent forillustrative purposes only) it can be seen that the gaps 408 betweenspacers 202 (in the first region 402 of pattern 304) are offset from thegaps 802 between the mandrels 104/mandrels 302 (in the third region 404of pattern 304). Thus, when the gaps 408 and gaps 802 are filled with aconductor to form electrodes of the device, those electrodes formed inthe gaps 408 and gaps 802 too will be offset from one another, i.e.,interleaved.

Namely, following from FIG. 9 , the gaps 408 between spacers 202 (in thefirst/front portion 402 of pattern 304) and the gaps 802 between themandrels 104/mandrels 302 (in the third/back portion 404 of pattern 304)are next filled with a conductor 1102. See FIG. 11 . Suitable conductorsinclude, but are not limited to, copper (Cu), tungsten (W), cobalt (Co)and/or ruthenium (Ru). A process such as sputtering, evaporation, orelectrochemical plating can be employed to deposit conductor 1102 intothe gaps 408 and the gaps 802. As shown in FIG. 11 , the conductor 1102overfills the gaps 408 and the gaps 802 and is then planarized to thetop of channel spacer 702. The conductor 1102 can be planarized using aprocess such as CMP.

As shown in FIG. 11 , the channel spacer 702 now separates the conductor1102 over the first/front portion 402 from the conductor 1102 over thethird/back portion 404 of pattern 304. The channel spacer 702 is thenselectively removed. See FIG. 12 . As shown in FIG. 12 , removal ofchannel spacer 702 forms a trench 1202 in between the conductor 1102over the first/front portion 402 and the conductor 1102 over thethird/back portion 404 of pattern 304.

As provided above, channel spacer 702 can be formed from acarbon-containing spacer material such as amorphous carbon. Amorphouscarbon is an ashable material. Thus, according to an exemplaryembodiment, channel spacer 702 is removed selective to conductor 1102using oxygen-containing plasma ashing.

Opening of trench 1202 in conductor 1102 exposes the underlying portionsof spacers 202 and mandrels 104/mandrels 302 in the second/centralportion 403 of the pattern 304. An etch is then used to remove theseportions of spacers 202 and mandrels 104/mandrels 302 through trench1202. See FIG. 13 . As shown in FIG. 13 , this etch step forms a channel1302 in between the first/front portion 402 and the third/back portion404 of the pattern 304. According to an exemplary embodiment, adirectional (anisotropic) etching process such as RIE is employed forthe channel etch. As provided above, the spacers 202 can be formed froma nitride material, and the mandrels 104/mandrels 302 can be formed froman oxide material. Thus, in that case, an oxide/nitride-selective RIE(or combination of RIE steps) can be used to pattern channel 1302through trench 1202. Based on the dimensions of channel spacer 702 (seeabove), according to an exemplary embodiment, channel 1302 is ananochannel having a width of from about 2 nm to about 10 nm and rangestherebetween.

The conductor 1102 is then recessed. See FIG. 14 . A process such as CMPor a metal-selective etch can be used to recess conductor 1102 down tospacers 202 (in the first/front portion 402 of the pattern 304) andmandrels 104/mandrels 302 (in the third/back portion 404 of the pattern304). Recessing the conductor 1102 forms an array of electrodes on bothsides of the channel 1302. Namely, as shown in FIG. 14 , firstelectrodes 1402 are present in between spacers 202 on a first side ofchannel 1302, and second electrodes 1404 are present in between mandrels104/mandrels 302 on a second/opposite side of channel 1302.

When viewed from the top-down (i.e., from viewpoint A), it can be seenthat the first electrodes 1402 are offset from second electrodes 1404across channel 1302. See FIG. 15 . This configuration is what isreferred to herein as ‘interleaving’ the electrodes.

For instance, if one were to visualize the structure without themandrels 104/mandrels 302 and spacers 202 (see FIG. 16 where mandrels104/mandrels 302 and spacers 202 are transparent for illustrativepurposes only) it can be seen that the first electrodes 1402 are offsetfrom second electrodes 1404 across channel 1302, i.e., interleaved.According to an exemplary embodiment, each of first/second electrodes1402/1404 has a width Welectrode of from about 5 nm to about 10 nm andranges therebetween, and a height Helectrode of from about 20 nm toabout 50 nm and ranges therebetween. See FIG. 16 .

As highlighted above, the present 3D device structures permit theelectro-kinetic control of individual molecules using the dipolesinherent in the subject material. See, for example, FIG. 17 . As isknown in the art, polar molecules have a partial negative end and apartial positive end. Dipole-dipole interactions occur when the partialpositive end of one molecule is attracted to the partial negative end ofanother molecule, and vice versa. These interactions can also be used tocontrol the orientation and movement of individual polar molecules withthe nanochannel.

For instance, as shown in FIG. 17 , during operation a field appliedselectively to portions of a polar molecule 1702 will electrokineticallyorient (see angle θ) and/or locomote (along x-direction) the polarmolecule 1702 in the channel 1302 as a result of dynamic electric fieldapplied to the first/second electrodes 1402/1404. Polar molecule 1702can be present in a fluid medium such as a solvent. Thus, in addition toelectrokinetics, a positive pressure of the fluid can also be employedto move molecule 1702 through channel 1302.

Advantageously, first/second electrodes 1402/1404 can be controlledindividually to locomote and/or orient polar molecule 1702. See, forexample, the electric field being applied dynamically to the electrodes1402/1404 on opposite sides of channel 1302. Further, as provided above,first/second electrodes 1402/1404 are offset from one another onopposite sides of the channel 1302. Interleaving the electrodes1402/1404 in this manner enables a much finer level of control andmanipulation of the molecule 1702.

Although illustrative embodiments of the present invention have beendescribed herein, it is to be understood that the invention is notlimited to those precise embodiments, and that various other changes andmodifications may be made by one skilled in the art without departingfrom the scope of the invention.

What is claimed is:
 1. A method of forming a device for molecularmanipulation, the method comprising: forming a pattern on a substrate ofalternating mandrels and spacers alongside the mandrels; selectivelyremoving the mandrels from a front portion of the pattern forming gapsbetween the spacers; selectively removing the spacers from a backportion of the pattern forming gaps between the mandrels; filling i) thegaps between the spacers with a conductor to form first electrodes andii) the gaps between the mandrels with the conductor to form secondelectrodes; and etching the mandrels and the spacers in a centralportion of the pattern to form a channel between the first electrodesand the second electrodes, wherein the first electrodes and the secondelectrodes are offset from one another across the channel.
 2. The methodof claim 1, wherein the mandrels comprise an oxide material.
 3. Themethod of claim 2, wherein the oxide material comprises undoped siliconoxide (SiOx).
 4. The method of claim 1, wherein the spacers comprise anitride material.
 5. The method of claim 4, wherein the nitride materialis selected from the group consisting of: nitride (SiN), siliconoxynitride (SiON), and combinations thereof.
 6. The method of claim 1,wherein the conductor is selected from the group consisting of: copper(Cu), tungsten (W), cobalt (Co), ruthenium (Ru), and combinationsthereof.
 7. The method of claim 1, further comprising: forming firstmandrels on the substrate; forming the spacers alongside the firstmandrels; and filling spaces between the spacers alongside adjacentfirst mandrels with a mandrel material to form second mandrels in thespaces.
 8. The method of claim 1, further comprising: forming a maskcovering the back portion and the central portion of the pattern; andselectively removing the mandrels from the front portion of the patternusing the mask.
 9. The method of claim 8, wherein the mask comprisesamorphous carbon.
 10. The method of claim 8, further comprising: fillingthe gaps between the spacers with a sacrificial material prior toselectively removing the spacers from the back portion of the pattern.11. The method of claim 10, wherein the sacrificial material is selectedfrom the group consisting of: amorphous silicon, poly-silicon, andcombinations thereof.
 12. The method of claim 1, further comprising:forming a channel spacer over the central portion of the pattern;filling the gaps between the spacers and the gaps between the mandrelswith the conductor; selectively removing the channel spacer forming atrench in the conductor over the central portion of the pattern; andetching the mandrels and the spacers in the central portion of thepattern through the trench to form the channel.
 13. The method of claim12, wherein the conductor overfills the gaps between the spacers and thegaps between the mandrels, and wherein the method further comprises:planarizing the conductor to a top of the channel spacer such that thechannel spacer separates the conductor over the front portion of thepattern from the conductor over the back portion of the pattern.
 14. Themethod of claim 13, further comprising: recessing the conductor down tothe spacers in the front portion of the pattern and down to the mandrelsin the back portion of the pattern.
 15. The method of claim 12, whereinthe channel spacer comprises amorphous carbon.
 16. The method of claim1, wherein the mandrels have a width of from about 5 nm to about nm andranges therebetween, and a pitch of from about 10 nm to about 20 nm. 17.The method of claim 1, wherein the spacers have a width of from about 5nm to about 10 nm.
 18. The method of claim 1, wherein the channelcomprises a nanochannel having a width of from about 2 nm to about 10nm.
 19. The method of claim 1, wherein the channel comprises a fluidicpassage.
 20. The method of claim 1, wherein the first electrodes and thesecond electrodes are interleaved rather than being directly oppositeone another across the channel.